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Name: FR 4121 (Ajax Mine Processing Plant) Author's Rating:
Author: Matt Marine Avg. User Rating: Not rated yet
Type: 4WD Difficulty: (Moderate 4WD)
Time: 1 hour Region: Southwest Arizona
Length: 1.43 miles total (one way) Elevation gain/loss/change: ~ +119 ft / -2ft / +117 ft (one way)
Type: Through trail (maybe - see description) Avg Elevation: 3800 ft
Best time to go: fall, spring, winter Fees: NA
Fitness rating: Low Educational Merit: Medium
Danger/fear rating: Medium Scenic Beauty: High
Hours of Operation: NA Last updated: February, 2015
Short Description: A short trip to the ruins of an old ore processing site
Geocaches: A few geocaches in the area: Cholla Hill; Jolly Roger; It's Mine!
References / Contact Information: Webs of Arivaca photo gallery;
Points of interest: Beautiful canyon, ore processing site, telegraph pole
Special Considerations: Although Forest Service MVUM shows trail is open, there is a locked gate on the south side. It appears you can go through the bypass, though this may not always be the case
How to get there: See Coches Well adventure for directions. Drive to WPT004 in the Coches Well trail (which is WPT001 here) and turn right onto FR4121.

Trail Description

Note: We did this trail after two days of almost continuous rain. I believe this canyon is usually dry. We just lucked out. The morning we went also had thick fog, which is unusual for Arizona. Due to these conditions, we found tons of cool spider webs. You can see a photo gallery of those by clicking here.

This is a super short 4WD trail off the Coches Well Ruins run that shouldn't be missed. The trail is more difficult than those on the Coches Well trail. It takes you to what I call the Ajax Mine Processing Site.

This area has many old foundations and stone ruins (not buildings though). The southern end of the trail rejoins FR216, but it is not clear on what's going on here. The Forest Service MVUM (Motor Vehicle Use Map) shows this road going through to FR216, but you will find a locked gate and a bypass here. It appears that at one point large boulders were placed near FR216 at the bypass, but access through the boulders seems valid given the Forest Service map. Use your best judgment.

General Information and History

I do not have any information on the ore processing site (at least that's what I think it was). I believe it is typical of these types of mining operations. They started off small many years ago, then moved elsewhere. Someone else came in years later with updated equipment and did some more work. This repeated itself a few times. We found one date on a foundation from the 1950s, but my guess was this was one of the most recent ventures. The area was most likely mined and used as a processing site in the 1800s and early 1900s.

Also in the area is what could be the remains of Arizona's first telegraph line: a weathered old wooden pole. As with many historical items, there are conflicting accounts of this.

A letter dated May 24, 1865 to the Surveyor General's Office in Sate Fe, New Mexico states the this telegraph line was the first in Arizona: "Sir: In my letter to your office from Tubac, date 13th March last, I gave you some account of my journey and the character of the country through which I had passed up to that date. On the 14th of March, in company with Dr. Locke, of the Santa Rita Mining Company, and several other gentleman, I visited the Cerro Colorado mines, about twenty-one miles westwardly from Tubac. M. O. Davidson, esq., superintendent, kindly furnished me with every facility for examining the mines and works, and gave me all the information asked concerning them. The Arizona Mining Company, the owners of these mines, are erecting reductions works here, and will soon be in readiness to commence reducing the rich ores of the Heintzelman and numerous other veins in this vicinity. The Enriguetta Mining Company, under the same superintendence, are also erecting works at the Enriguetta mines, about thirteen miles southwest from the Cerro Colorado. I was shown some very rich ores from these mines, but did not visit them. The superintendent has had a telegraph line erected, connecting these two mining haciendas-the first and only line of telegraph in that Territory: there is none in New Mexico."

But, from Arizona Place Names, by Will Croft Barnes, puts some doubt on the above claim. "First Telegraph Line into Territory. Fish claims that, "the first line was owned by Cerro Colorado Mine Company and ran from Frowita to Cerro Colorado mine. This was at an early date not given. He gives no authority for the statement. Its correctness is problematical. Undoubtedly the first telegraph line in Arizona was the extension of the Desert Telegraph Line; a Mormon church affair, from Kanab, Utah, to Pipe springs, Arizona, 1871. Miss Ella Stewart was the operator. She later became the wife of D.K. Udall, of Mesa."

Whatever the case, the pole is old and needs to be treated with care. None of the line or other poles remain. Note: I purposely do not give out the specific location of the telegraph pole.

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The Trail

See Coches Well 4WD trip for information on how to get to WPT001 (which is labeled at WPT004 in that adventure). At Waypoint WPT001, turn off FR216 onto FR4121. You will begin to follow the wash to your right a little more closely. After about 0.45 miles, you will come to a Y-intersection at WPT002.

The right leads to Ajax Mine. There is not a lot left of the mine. Continue straight on FR4121 to go to the processing plant.

The next section of the trail is a little rocky and is the most difficult of the short trail. It also crosses the wash in a few areas, which was fun when there was water flowing through.

Drive another 0.45 miles until you begin to see all the foundations at the old ore processing site at WPT003. There's large parking areas here and foundations and ruins on both sides of the road. I have also included what looked like the ruins to a two room building that I found on Google Earth after we did this run about 600 feet before the ruins. See Maps page for a Google Earth image of the site and the coordinates of the ruins.

When you're done exploring the site, you can either turn around and go back the way you came in, or try to go out the southern route. As stated earlier, the Forest Service MVUM shows this trail as open, but there's a locked gate at WPT004 and a bypass.

To continue south, keep driving along FR4122 for another 0.3 miles until you reach the locked gate at WPT004. Take a sharp left here, go up the hill and the curve right as the road intersects the main road at WPT005. You will need to go between two large boulders placed on the side of the road.

Once you're back on the road (no matter which way you exited), take a right to head further down south, or a left to go back to Arivaca.

Have fun and be safe!

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Have you been on this adventure? What did you think? Comments and updates welcome by clicking here. You can also rate this adventure by clicking here.

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